Skip to main content

Full text of "Practical Organic Chemistry"

See other formats


consists of azoxybenzene mixed with aniline and a little un-
changed nitrobenzene, is distilled in steam, which removes the
impurities. The residue then solidifies on cooling, and is filtered,
dried, and recrystallised. Yield 1 1 grams (6070 per cent, of
the theory) (Elbs, Electrolytic Preparations, trans, by R. S.
Mutton, p. 76).


Azobeiizene, CGH5N:N.CcHf,

Mitscherlich, Annalcn^ 1834,   12, 311.

5 grms. azoxybenzene.
15            iron filings.

The azoxybenzene and iron filings, both of which must be
carefully dried on the water-bath, are powdered together and
distilled from a small retort, which is conveniently made by
blowing a large bulb on the end of a piece of rather wide
tubing i-i~ cm. inside diameter, and then allowing the bulb
whilst hot to bend over. The mixture is carefully heated, the
burner being moved about until the contents are thoroughly
hot, and then the mixture is more strongly heated until nothing-
further distils. The distillate, which forms a solid, dark- red
mass, is washed with a little dilute hydrochloric acid and water,
and then pressed on a porous plate. It is crystallised from
ligroin, in which it is very soluble.

QH.N   N.C0H6 + Fe = CGH;,N : N.C0HS + FeO.


Properties.  Red plates; m. p. 6SJ; b. p. 295. See Appendix ^
P- 274-
Azobenzene from Nitrobenzene by Electrolysis. A
good, yield of azobenzene can be obtained by the electrolytic
reduction of nitrobenzene in alcoholic solution. The apparatus
is similar to that shown in Fig. 77, p. 144, but in the present
case the cathode chamber is the outer vessel, which should be a
deep, narrow glass cylinder or beaker. The cathode liquid is
a solution of 20 grams nitrobenzene and 5 grams sodium acetate
crystals in 200 c.c. 70 per cent, spirit. The cathode is a cylinder
of nickel gauze. A large porous cell forms the anode chamber,
COHEN'S ADV. P. o. c.                                             L